The screen goes dark, or the browser freezes, or the timer keeps running while the page will not load the next question. When the machine comes back the session is locked, or it reopens on question 1 with 22 minutes already gone, or a proctoring warning says the session was interrupted. Nobody at the other end answers, and there is no record anywhere of what happened.
An online assessment taken from home or a cyber cafe in a Tier 2 or Tier 3 town, on a mains-powered desktop or a laptop with a tired battery, on a connection shared with the rest of the house. Common triggers: a scheduled load shedding slot, a router reboot, a Windows update that grabs the machine mid-test, a laptop lid setting that sleeps the session, or a mobile hotspot that runs out of data. Linked module: 6.2 (Online assessment prep).
There are two separate failures here, and only one of them is the power cut.
The first is the interruption itself, and it is not rare. In many towns a 90-minute window with no supply interruption is not something you can assume; it is something you arrange. The same is true of the connection, of the room, and of the machine's own habits.
The second failure is the one that actually costs the offer: no plan for the minute after. The usual panic sequence is to close the browser, clear cookies, open the link again in a new tab, and try a different device, all within four minutes. Every one of those actions can look like a second session to the platform, and several platforms lock an assessment after repeated re-entry because that pattern is also what cheating looks like. The student then has no timestamp, no screenshot, no support ticket, and no way to show that a power cut and not a person caused the gap.
The third thing to understand is what the platform can and cannot do. Many timed tests support a resume that restores your answered questions and the remaining clock, some do not, and the rules for a re-test are set by the company rather than by you. We cannot tell you which platform behaves which way, and nobody should. The instructions email you were sent states the policy and gives a support contact, and that email is the only source that governs your test.
A checklist run before the test, and a written first move for the moment it happens.
Before the test, the night before and again 30 minutes prior
The moment it breaks, in this order
If the session stays locked, the request you make is a re-test slot, sent with the evidence attached. That request is often granted and is never granted to somebody with no record.
Treat the checklist as part of the test, not as an optional extra, and run it for every practice mock as well so that it is habit by the day it matters. Book test slots away from known outage windows and away from peak network hours in your building. Take at least one full practice mock on the hotspot alone, so you know the fallback actually works under load. Keep one folder with your identity documents, candidate IDs, instruction emails and screenshots, because the second time this happens you will want the first write-up to point at.
Q: "Tell me about a time something outside your control went wrong." This is a strong answer if you tell it as a process rather than as bad luck. Name the failure, name what you had prepared in advance, describe the first move and why it was that one, show the evidence you captured within five minutes, and finish with the outcome. Interviewers hiring for anything near production are listening for exactly this shape: you cannot prevent every incident, so what they want to know is whether you keep records and act in a fixed order while it is happening.